Allow FPs to elevate default precision for the entire fragment program

Currently, GrConfigConversionEffect is able to round-trip on many mobile
GPUs because it uses highp for all intermediate variables (including the
texture fetch result). Separating the texture sample into a different
processor breaks that.

This is a blunt instrument, not to be used lightly.

Bug: skia:
Change-Id: I2ab365e3da79628069e2eb727c43c2bf45bfd789
Reviewed-on: https://skia-review.googlesource.com/10162
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/gpu/GrGeometryProcessor.h b/src/gpu/GrGeometryProcessor.h
index 2711b9a608..e5222bf80a 100644
--- a/src/gpu/GrGeometryProcessor.h
+++ b/src/gpu/GrGeometryProcessor.h
@@ -51,6 +51,7 @@ protected:
      */
     const Attribute& addVertexAttrib(const char* name, GrVertexAttribType type,
                                      GrSLPrecision precision = kDefault_GrSLPrecision) {
+        precision = (kDefault_GrSLPrecision == precision) ? kMedium_GrSLPrecision : precision;
         fAttribs.emplace_back(name, type, precision);
         fVertexStride += fAttribs.back().fOffset;
         return fAttribs.back();